Measured vs Navigated Techniques in Total Hip Arthroplasty

Accuracy in aChieving Optimum reconstrUction: Measured- vs. Navigation- Techniques in Hip Arthroplasty

Accurate reconstruction of the native hip parameters following total hip arthroplasty is associated with improved outcome. In order to improve ability for optimum reconstruction, 3-D templating software can be utilized that provide detailed information regarding native anatomy. In order to achieve reconstruction within acceptable parameters as per pre-operative plan, some surgeons propose the use of intra-operative devices that measure component orientation and joint reconstruction ("Measured-THA"), whilst others propose the use of navigation tools ("Navigation-THA). Both techniques have shown superiority compared to the most commonly used "freehand" technique, but no prior study has assessed for superiority between these 2 techniques. Furthermore, to-date assessment of post-operative reconstruction has not been tested in detail as post-THA assessments are based on radiographs which provide incomplete, 2-dimensional, assessments and are lacking the important axial plane reconstruction parameters. The aims of this prospective, randomized, trial are to 1. appraise the ability to achieve the pre-operative 3-D plan (as per FormusLab) through a comparison of pre-op plan to post-operative reconstruction; 2. compare ability to accurately reconstruct hip following THA between "navigated-" (IntelliJoint®) and "measured-" techniques; and in doing so it will also 3. assess the accuracy of the intra-operative assessments of reconstruction through a comparison of objective (i.e. measured) intra-operative assessments with the post-operative reconstructions achieved.

Inclusion Criteria:

• Patients who are signed for a THA for primary or secondary osteoarthritis without overt deformity that would require revision type implants and with good enough bone quality to be listed for uncemented component implantation.

Exclusion Criteria:

• Secondary OA due to Dysplasia (Hartofilakidis >1)
• Avascular necrosis of the hip with destruction of joint structure
• Sequelae of Pediatric deformity with abnormal anatomy
• Cemented fixation of femur or acetabulum
• Previous arthroplasty-type procedure
• Previous septic arthritis of the hip